This paper shows that just taking a picture of the carbon preform can be a powerful detection method of missing rod. The poor quality of the carbon preforms including missing rods cannot provide tailored composite to meet desired properties. By the way, the carbon preform is manufactured manually now and often there happen a mistake that a carbon rod is omitted. Therefore, an effective solution for guaranteeing the quality of the carbon preform is needed. For that reason, this paper proposes new inspection method that can detect the missing rods of multidirectional carbon preform. This method utilized some image processing techniques to simplify the image of carbon preform. In this method, the carbon preform image is modified so that the carbon rods and background can be easily separated. Thus, this new method found all missing rods and marked missing space with red circle. Moreover, because the inspection method suggested in this paper can be easily converted into the form of software, it is expected to be applied effectively to the fields of manufacture of the multidirectional carbon preform.